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16#include <linux/netdevice.h>
17#include <linux/export.h>
18
19#include <net/fib_rules.h>
20#include <net/ipv6.h>
21#include <net/addrconf.h>
22#include <net/ip6_route.h>
23#include <net/netlink.h>
24
25struct fib6_rule {
26 struct fib_rule common;
27 struct rt6key src;
28 struct rt6key dst;
29 u8 tclass;
30};
31
32struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
33 int flags, pol_lookup_t lookup)
34{
35 struct fib_lookup_arg arg = {
36 .lookup_ptr = lookup,
37 .flags = FIB_LOOKUP_NOREF,
38 };
39
40 fib_rules_lookup(net->ipv6.fib6_rules_ops,
41 flowi6_to_flowi(fl6), flags, &arg);
42
43 if (arg.result)
44 return arg.result;
45
46 dst_hold(&net->ipv6.ip6_null_entry->dst);
47 return &net->ipv6.ip6_null_entry->dst;
48}
49
50static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
51 int flags, struct fib_lookup_arg *arg)
52{
53 struct flowi6 *flp6 = &flp->u.ip6;
54 struct rt6_info *rt = NULL;
55 struct fib6_table *table;
56 struct net *net = rule->fr_net;
57 pol_lookup_t lookup = arg->lookup_ptr;
58
59 switch (rule->action) {
60 case FR_ACT_TO_TBL:
61 break;
62 case FR_ACT_UNREACHABLE:
63 rt = net->ipv6.ip6_null_entry;
64 goto discard_pkt;
65 default:
66 case FR_ACT_BLACKHOLE:
67 rt = net->ipv6.ip6_blk_hole_entry;
68 goto discard_pkt;
69 case FR_ACT_PROHIBIT:
70 rt = net->ipv6.ip6_prohibit_entry;
71 goto discard_pkt;
72 }
73
74 table = fib6_get_table(net, rule->table);
75 if (table)
76 rt = lookup(net, table, flp6, flags);
77
78 if (rt != net->ipv6.ip6_null_entry) {
79 struct fib6_rule *r = (struct fib6_rule *)rule;
80
81
82
83
84
85 if ((rule->flags & FIB_RULE_FIND_SADDR) &&
86 r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
87 struct in6_addr saddr;
88
89 if (ipv6_dev_get_saddr(net,
90 ip6_dst_idev(&rt->dst)->dev,
91 &flp6->daddr,
92 rt6_flags2srcprefs(flags),
93 &saddr))
94 goto again;
95 if (!ipv6_prefix_equal(&saddr, &r->src.addr,
96 r->src.plen))
97 goto again;
98 flp6->saddr = saddr;
99 }
100 goto out;
101 }
102again:
103 ip6_rt_put(rt);
104 rt = NULL;
105 goto out;
106
107discard_pkt:
108 dst_hold(&rt->dst);
109out:
110 arg->result = rt;
111 return rt == NULL ? -EAGAIN : 0;
112}
113
114
115static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
116{
117 struct fib6_rule *r = (struct fib6_rule *) rule;
118 struct flowi6 *fl6 = &fl->u.ip6;
119
120 if (r->dst.plen &&
121 !ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen))
122 return 0;
123
124
125
126
127
128
129 if (r->src.plen) {
130 if (flags & RT6_LOOKUP_F_HAS_SADDR) {
131 if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr,
132 r->src.plen))
133 return 0;
134 } else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
135 return 0;
136 }
137
138 if (r->tclass && r->tclass != ((ntohl(fl6->flowlabel) >> 20) & 0xff))
139 return 0;
140
141 return 1;
142}
143
144static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
145 FRA_GENERIC_POLICY,
146};
147
148static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
149 struct fib_rule_hdr *frh,
150 struct nlattr **tb)
151{
152 int err = -EINVAL;
153 struct net *net = sock_net(skb->sk);
154 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
155
156 if (rule->action == FR_ACT_TO_TBL) {
157 if (rule->table == RT6_TABLE_UNSPEC)
158 goto errout;
159
160 if (fib6_new_table(net, rule->table) == NULL) {
161 err = -ENOBUFS;
162 goto errout;
163 }
164 }
165
166 if (frh->src_len)
167 nla_memcpy(&rule6->src.addr, tb[FRA_SRC],
168 sizeof(struct in6_addr));
169
170 if (frh->dst_len)
171 nla_memcpy(&rule6->dst.addr, tb[FRA_DST],
172 sizeof(struct in6_addr));
173
174 rule6->src.plen = frh->src_len;
175 rule6->dst.plen = frh->dst_len;
176 rule6->tclass = frh->tos;
177
178 err = 0;
179errout:
180 return err;
181}
182
183static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
184 struct nlattr **tb)
185{
186 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
187
188 if (frh->src_len && (rule6->src.plen != frh->src_len))
189 return 0;
190
191 if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
192 return 0;
193
194 if (frh->tos && (rule6->tclass != frh->tos))
195 return 0;
196
197 if (frh->src_len &&
198 nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
199 return 0;
200
201 if (frh->dst_len &&
202 nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
203 return 0;
204
205 return 1;
206}
207
208static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
209 struct fib_rule_hdr *frh)
210{
211 struct fib6_rule *rule6 = (struct fib6_rule *) rule;
212
213 frh->dst_len = rule6->dst.plen;
214 frh->src_len = rule6->src.plen;
215 frh->tos = rule6->tclass;
216
217 if ((rule6->dst.plen &&
218 nla_put(skb, FRA_DST, sizeof(struct in6_addr),
219 &rule6->dst.addr)) ||
220 (rule6->src.plen &&
221 nla_put(skb, FRA_SRC, sizeof(struct in6_addr),
222 &rule6->src.addr)))
223 goto nla_put_failure;
224 return 0;
225
226nla_put_failure:
227 return -ENOBUFS;
228}
229
230static u32 fib6_rule_default_pref(struct fib_rules_ops *ops)
231{
232 return 0x3FFF;
233}
234
235static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
236{
237 return nla_total_size(16)
238 + nla_total_size(16);
239}
240
241static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = {
242 .family = AF_INET6,
243 .rule_size = sizeof(struct fib6_rule),
244 .addr_size = sizeof(struct in6_addr),
245 .action = fib6_rule_action,
246 .match = fib6_rule_match,
247 .configure = fib6_rule_configure,
248 .compare = fib6_rule_compare,
249 .fill = fib6_rule_fill,
250 .default_pref = fib6_rule_default_pref,
251 .nlmsg_payload = fib6_rule_nlmsg_payload,
252 .nlgroup = RTNLGRP_IPV6_RULE,
253 .policy = fib6_rule_policy,
254 .owner = THIS_MODULE,
255 .fro_net = &init_net,
256};
257
258static int __net_init fib6_rules_net_init(struct net *net)
259{
260 struct fib_rules_ops *ops;
261 int err = -ENOMEM;
262
263 ops = fib_rules_register(&fib6_rules_ops_template, net);
264 if (IS_ERR(ops))
265 return PTR_ERR(ops);
266 net->ipv6.fib6_rules_ops = ops;
267
268
269 err = fib_default_rule_add(net->ipv6.fib6_rules_ops, 0,
270 RT6_TABLE_LOCAL, 0);
271 if (err)
272 goto out_fib6_rules_ops;
273
274 err = fib_default_rule_add(net->ipv6.fib6_rules_ops,
275 0x7FFE, RT6_TABLE_MAIN, 0);
276 if (err)
277 goto out_fib6_rules_ops;
278
279out:
280 return err;
281
282out_fib6_rules_ops:
283 fib_rules_unregister(ops);
284 goto out;
285}
286
287static void __net_exit fib6_rules_net_exit(struct net *net)
288{
289 fib_rules_unregister(net->ipv6.fib6_rules_ops);
290}
291
292static struct pernet_operations fib6_rules_net_ops = {
293 .init = fib6_rules_net_init,
294 .exit = fib6_rules_net_exit,
295};
296
297int __init fib6_rules_init(void)
298{
299 return register_pernet_subsys(&fib6_rules_net_ops);
300}
301
302
303void fib6_rules_cleanup(void)
304{
305 unregister_pernet_subsys(&fib6_rules_net_ops);
306}
307
